java - ProcessBuilder - 没有这样的文件或目录(但 Runtime.exec() 有效)

Question

为什么我在这两种情况下会遇到不同的行为？我错过了什么吗？

命令:

new ProcessBuilder().directory(
                    Paths.get(System.getProperty("user.dir")).toFile())
                    .command("/usr/bin/java -Djava.library.path=/Users/myusername/myproject/lib/DynamoDBLocal_lib/ -jar /Users/myusername/myproject/lib/DynamoDBLocal.jar  -sharedDb").start();

堆栈跟踪:

Exception in thread "main" java.lang.RuntimeException: java.io.IOException: Cannot run program "/usr/bin/java -Djava.library.path=/Users/myusername/myproject/lib/DynamoDBLocal_lib/ -jar /Users/myusername/myproject/lib/DynamoDBLocal.jar  -sharedDb" (in directory "/Users/myusername/myproject"): error=2, No such file or directory
    at com.comcast.tvx.app.xreserver.Main.exec(Main.java:47)
    at com.comcast.tvx.app.xreserver.Main.main(Main.java:16)
Caused by: java.io.IOException: Cannot run program "/usr/bin/java -Djava.library.path=/Users/myusername/myproject/lib/DynamoDBLocal_lib/ -jar /Users/myusername/myproject/lib/DynamoDBLocal.jar  -sharedDb" (in directory "/Users/myusername/myproject"): error=2, No such file or directory
    at java.lang.ProcessBuilder.start(ProcessBuilder.java:1048)
    at com.comcast.tvx.app.xreserver.Main.exec(Main.java:44)
    ... 1 more
Caused by: java.io.IOException: error=2, No such file or directory
    at java.lang.UNIXProcess.forkAndExec(Native Method)
    at java.lang.UNIXProcess.<init>(UNIXProcess.java:248)
    at java.lang.ProcessImpl.start(ProcessImpl.java:134)
    at java.lang.ProcessBuilder.start(ProcessBuilder.java:1029)
    ... 2 more

失败案例中的环境:

{PATH=/usr/bin:/bin:/usr/sbin:/sbin
JAVA_STARTED_ON_FIRST_THREAD_1074=1
SHELL=/bin/zsh
SECURITYSESSIONID=186a4
USER=myusername
JAVA_MAIN_CLASS_25188=com.comcast.tvx.app.xreserver.Main
APP_ICON_1074=../Resources/Eclipse.icns
COMMAND_MODE=unix2003
TMPDIR=/var/folders/t_/dlj2wfdj0bx2xl6mnnqmxyhj99pf4b/T/
SSH_AUTH_SOCK=/tmp/launch-Bhd1It/Listeners
DISPLAY=/tmp/launch-PuSx66/org.macosforge.xquartz:0
__CF_USER_TEXT_ENCODING=0x529B388B:0:0
Apple_PubSub_Socket_Render=/tmp/launch-hB7zpQ/Render
__CHECKFIX1436934=1
LOGNAME=myusername
HOME=/Users/myusername}

更多信息

当我使用 Runtime.exec() 执行此操作时，环境看起来相同但我没有收到错误:

命令:

Runtime.getRuntime().exec("/usr/bin/java -Djava.library.path=/Users/myusername/myproject/lib/DynamoDBLocal_lib/ -jar /Users/myusername/myproject/lib/DynamoDBLocal.jar  -sharedDb")

后续案例中的环境:

{PATH=/usr/bin:/bin:/usr/sbin:/sbin
JAVA_STARTED_ON_FIRST_THREAD_1074=1
SHELL=/bin/zsh
JAVA_MAIN_CLASS_25360=com.comcast.tvx.app.xreserver.Main
SECURITYSESSIONID=186a4
USER=myusername
APP_ICON_1074=../Resources/Eclipse.icns
COMMAND_MODE=unix2003
TMPDIR=/var/folders/t_/dlj2wfdj0bx2xl6mnnqmxyhj99pf4b/T/
SSH_AUTH_SOCK=/tmp/launch-Bhd1It/Listeners
DISPLAY=/tmp/launch-PuSx66/org.macosforge.xquartz:0
__CF_USER_TEXT_ENCODING=0x529B388B:0:0
Apple_PubSub_Socket_Render=/tmp/launch-hB7zpQ/Render
__CHECKFIX1436934=1
LOGNAME=myusername
HOME=/Users/myusername}

Answer 1

尝试改变这一行:

.command("/usr/bin/java -Djava.library.path=/Users/myusername/myproject/lib/DynamoDBLocal_lib/ -jar /Users/myusername/myproject/lib/DynamoDBLocal.jar  -sharedDb").start();

到(一直向右滚动以查看差异):

.command("/usr/bin/java -Djava.library.path=/Users/myusername/myproject/lib/DynamoDBLocal_lib/ -jar /Users/myusername/myproject/lib/DynamoDBLocal.jar  -sharedDb".split("\\s+")).start();

解释:command() 的输入应该是一个字符串数组(或列表)，每个字符串都是另一个参数(或“ token ”)。它不应包含空格!

来自docs :

a command, a list of strings which signifies the external program file to be invoked and its arguments, if any. Which string lists represent a valid operating system command is system-dependent. For example, it is common for each conceptual argument to be an element in this list, but there are operating systems where programs are expected to tokenize command line strings themselves - on such a system a Java implementation might require commands to contain exactly two elements.